If someone is raking up something unpleasant or embarrassing that happened in the past, they are talking about it when you would prefer them not to mention it.
Raking up the past won't help anyone. [VERBPARTICLE noun]
[Also VERB noun PARTICLE]
See full dictionary entry for rake
rake up in British English
verb
(tr, adverb)
to revive, discover, or bring to light (something forgotten)
to rake up an old quarrel
rake up in American English
to uncover facts or gossip about (the past, a scandal, etc.)
See full dictionary entry for rake
Examples of 'rake up' in a sentence
rake up
I can understand she doesn't want to rake up the past, but if it has to happen, so be it.
Penn, John UNTO THE GRAVE
Men would say `Like mother, like daughter, "would rake up all the old gossip about you and Will de Braose.
Penman, Sharon HERE BE DRAGONS
Yeoman Jones looked the handsome dark-haired rake up and down.
Fidelis Morgan THE RIVAL QUEENS: A COUNTESS ASHBY DE LA ZOUCHE MYSTERY (2002)